Jay D. Keasling, a UC Berkeley chemical engineer and leader in the new field of synthetic biology, has won the prestigious Heinz Award of $250,000 for developing an inexpensive way to mass-produce a plant-based drug to treat malaria.

The drug from the plant is called artemisinin. Using genetic engineering, Keasling combined the plant's genes with genes from yeast and a common gut bacterium. The result was to turn the bacteria into microbial "factories" that produce unlimited, low-cost versions of the antimalaria drug.

The Berkeley scientist also created a company in Emeryville called Amyris Biotechnology, which has licensed the nonprofit Institute for One World Health to oversee its manufacture and distribution around the world.

Artemisinin, a weed known as sweet wormwood, is called Qinghaosu in China, and has been used there against malaria for centuries. But difficulties in growing and preparing it have made it extremely expensive for treating a disease that now kills more than 500,000 people a year - most of them children and 80 percent of them in Africa.

Keasling began tackling the problem by artificially producing artemisinin through genetic engineering 10 years ago, and in 2004 a $42.5 million grant from the Bill and Melinda Gates Foundation financed laboratory research and successful mass-production of the drug.

"Dr. Keasling's research is revealing how we can use natural systems to produce cheaper, more environmentally friendly compounds for everything from antimalaria drugs to biofuels," Teresa Heinz, chairwoman of the Heinz Family Foundation, said Wednesday, when the award was announced.

At the Institute, he now leads a research effort in genetic engineering aimed at converting the world's agricultural wastes and acres of useless plants like switchgrass into mass-produced new fuels that would replace oil.

As to how he would use his $250,000 Heinz Award, his answer was brief:

"I'll give it away to some nonprofit, but I haven't decided which one yet," he said.